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<b>DbEnv::log_put</b>
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<b><pre>
#include &lt;db_cxx.h&gt;
<p>
int
DbEnv::log_put(DbLsn *lsn, const Dbt *data, u_int32_t flags);
</pre></b>
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<b>Description: DbEnv::log_put</b>
<p>The DbEnv::log_put method appends records to the log.  The <a href="../api_cxx/lsn_class.html">DbLsn</a> of
the put record is returned in the <b>lsn</b> parameter.</p>
<p>The DbEnv::log_put method
either returns a non-zero error value
or throws an exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</p>
<b>Parameters</b> <br>
 <b>data</b><ul compact><li>The <b>data</b> parameter is the record to write to the log.
<p>The caller is responsible for providing any necessary structure to
<b>data</b>.  (For example, in a write-ahead logging protocol, the
application must understand what part of <b>data</b> is an operation
code, what part is redo information, and what part is undo information.
In addition, most transaction managers will store in <b>data</b> the
<a href="../api_cxx/lsn_class.html">DbLsn</a> of the previous log record for the same transaction, to
support chaining back through the transaction's log records during
undo.)</p></ul>
 <b>flags</b><ul compact><li>The <b>flags</b> parameter must be set to 0 or
the following value:
<br>
<b><a name="DB_FLUSH">DB_FLUSH</a></b><ul compact><li>The log is forced to disk after this record is written, guaranteeing
that all records with <a href="../api_cxx/lsn_class.html">DbLsn</a> values less than or equal to the
one being "put" are on disk before DbEnv::log_put returns.</ul>
<br></ul>
 <b>lsn</b><ul compact><li>The <b>lsn</b> parameter references memory into which
 the <a href="../api_cxx/lsn_class.html">DbLsn</a> of the put record is copied.</ul> 
<br>
<br><b>Errors</b>
<p>The <a href="../api_cxx/log_flush.html">DbEnv::log_flush</a> method
may fail and throw
<a href="../api_cxx/except_class.html">DbException</a>,
encapsulating one of the following non-zero errors, or return one of
the following non-zero errors:</p>
<br>
<b>EINVAL</b><ul compact><li>If the record to be logged is larger than the maximum log record; or if an
invalid flag value or parameter was specified.</ul>
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<br><b>Class</b>
<a href="../api_cxx/env_class.html">DbEnv</a>, <a href="../api_cxx/logc_class.html">DbLogc</a>, <a href="../api_cxx/lsn_class.html">DbLsn</a>
<br><b>See Also</b>
<a href="../api_cxx/log_list.html">Logging Subsystem and Related Methods</a>
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